[PATCH kernel v12 30/34] powerpc/iommu/ioda2: Add get_table_size() to calculate the size of future table
From: Alexey Kardashevskiy <hidden>
Date: 2015-06-05 06:38:53
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
This adds a way for the IOMMU user to know how much a new table will use so it can be accounted in the locked_vm limit before allocation happens. This stores the allocated table size in pnv_pci_ioda2_get_table_size() so the locked_vm counter can be updated correctly when a table is being disposed. This defines an iommu_table_group_ops callback to let VFIO know how much memory will be locked if a table is created. Signed-off-by: Alexey Kardashevskiy <redacted> Reviewed-by: David Gibson <redacted> --- Changes: v10: * s/ROUND_UP/_ALIGN_UP/ * fixed rounding up for @entries_shift (used to use ROUND_UP) v9: * reimplemented the whole patch --- arch/powerpc/include/asm/iommu.h | 5 +++++ arch/powerpc/platforms/powernv/pci-ioda.c | 34 +++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+)
diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index e554175..9d37492 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h@@ -99,6 +99,7 @@ struct iommu_table { unsigned long it_size; /* Size of iommu table in entries */ unsigned long it_indirect_levels; unsigned long it_level_size; + unsigned long it_allocated_size; unsigned long it_offset; /* Offset into global table */ unsigned long it_base; /* mapped address of tce table */ unsigned long it_index; /* which iommu table this is */
@@ -147,6 +148,10 @@ extern struct iommu_table *iommu_init_table(struct iommu_table * tbl, struct iommu_table_group; struct iommu_table_group_ops { + unsigned long (*get_table_size)( + __u32 page_shift, + __u64 window_size, + __u32 levels); long (*create_table)(struct iommu_table_group *table_group, int num, __u32 page_shift,
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 612ab23..1cb96f0 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c@@ -2073,6 +2073,38 @@ static long pnv_pci_ioda2_create_table(struct iommu_table_group *table_group, } #ifdef CONFIG_IOMMU_API +static unsigned long pnv_pci_ioda2_get_table_size(__u32 page_shift, + __u64 window_size, __u32 levels) +{ + unsigned long bytes = 0; + const unsigned window_shift = ilog2(window_size); + unsigned entries_shift = window_shift - page_shift; + unsigned table_shift = entries_shift + 3; + unsigned long tce_table_size = max(0x1000UL, 1UL << table_shift); + unsigned long direct_table_size; + + if (!levels || (levels > POWERNV_IOMMU_MAX_LEVELS) || + (window_size > memory_hotplug_max()) || + !is_power_of_2(window_size)) + return 0; + + /* Calculate a direct table size from window_size and levels */ + entries_shift = (entries_shift + levels - 1) / levels; + table_shift = entries_shift + 3; + table_shift = max_t(unsigned, table_shift, PAGE_SHIFT); + direct_table_size = 1UL << table_shift; + + for ( ; levels; --levels) { + bytes += _ALIGN_UP(tce_table_size, direct_table_size); + + tce_table_size /= direct_table_size; + tce_table_size <<= 3; + tce_table_size = _ALIGN_UP(tce_table_size, direct_table_size); + } + + return bytes; +} + static long pnv_pci_ioda2_unset_window(struct iommu_table_group *table_group, int num) {
@@ -2116,6 +2148,7 @@ static void pnv_ioda2_release_ownership(struct iommu_table_group *table_group) } static struct iommu_table_group_ops pnv_pci_ioda2_ops = { + .get_table_size = pnv_pci_ioda2_get_table_size, .create_table = pnv_pci_ioda2_create_table, .set_window = pnv_pci_ioda2_set_window, .unset_window = pnv_pci_ioda2_unset_window,
@@ -2227,6 +2260,7 @@ static long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset, page_shift); tbl->it_level_size = 1ULL << (level_shift - 3); tbl->it_indirect_levels = levels - 1; + tbl->it_allocated_size = offset; pr_devel("Created TCE table: ws=%08llx ts=%lx @%08llx\n", window_size, tce_table_size, bus_offset);
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2.4.0.rc3.8.gfb3e7d5